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CLASS P I S C E S. 



ORDER AC ANTH OPTER YGI A. 



CLASS IV. P I S C E S. 



This class of vertebrate Animals are inhabitants of the waters, in which element they live, move, and in general obtain their prey. 

 They are oviparous, have a double circulation, and breathe through the medium of water, for which they are provided with 

 branchiae or gills an apparatus which separates the oxygen from the atmospheric air. They urge themselves forward by striking 

 the water right and left with their tail. Their fins, answering to arms, are called pectorals, and those corresponding with feet are 

 named ventrals. They are classed into two series Bony Fishes and Cartilaginous Fishes. 



BONY FISHES. PISCES OSSEI. 



Bos? or ordinary Fishes are characterised by having bones in the skeleton ; 

 they are divided into Spinous arid Soft-finned Fishes. 



ORDER I. ACANTHOPTERYGIA. SPINE-FINNED. 



THE Spine-finned Fishes include by far the greater number of Ordinary 

 Fishes. The families of which they are composed have been arranged into 

 one Order; they are characterised by spinal rays in the first dorsal, if 

 there be more than one dorsal, or spinal rays in the first part if there is 

 one dorsal only ; in some, instead of a first dorsal, there are free spines 

 without any connecting membranes. The first rays of the anal fin are 

 also spinous, and the ventrals generally have at least one spinal ray. 



ILLUSTRATIVE EXAMPLES. 



PLATE 1. 

 Family PERCH; Percaida. 



Genera. 



Perca - - 



Trachinus - 



Mullus - - 



Species. 



Common Name. 



- - Fluviatilis - - - - Perch. 



- - Draco ------ Common Weever. 



- - Barbatus ----- Smaller Red-beard. 



Family GURNALS; Trigloida. 



The principal distinction between the family Trigloida and Percoida con- 

 sists in the extension of the suborbital bone (more or less) over the cheek 

 of the former family, and in its articulation with the operculum. 



Trigla ... - Gurnaidus - - - - Red Gurnard. 

 Dactylopterus - - Mediterraneus. 



Family MAIGRES; Scicenida. 



The Maigres differ from the Perches in the absence of teeth on the 

 vomer or palate : like the Perch family, their preorculum and operculum 

 are both notched. 



Scuena - ... Umbra. 



Amphiprion - - Ephippium - - - - Saddle-fish. 



CHARACTERS OF THE GENERA. 



1. PERCA (Gr. irtpioj, perch, so named because spotted with black). 

 Body oblong, compressed, generally covered with tough scales; mouth 

 tolerably wide, and teeth in the jaws, transversely across the vomer, gene- 

 rally, also, longitudinally in the palatines, and on the pharyngeal bones and 

 denticles of the gills ; gills wide, the membrane supported by rays never 

 less than five, rarely more than seven ; the opercule and preopercule differ- 

 ently armed ; ventral fins under the pectorals, and two dorsal fins generally 

 a little apart from each other. 



2. TRACHINUS. Head and body lengthy and compressed ; eyes near 

 the tip of the short muzzle ; gape obliquely upwards ; bands of villous 

 teeth on both jaws, on the front of the vomer, on the palatine and ptery- 

 goid bones ; opercule armed with one long spine ; supra scapular bone 

 dentated ; first dorsal fin very short, and entirely supported with very sharp 

 spines ; second long, and all its rays soft ; pectoral fins very large. 



3. MULLUS. Body oblong, head of moderate size and sloping gills; no 

 teeth in the upper jaw, but large flat teeth in the palate ; eyes large and 

 near each other ; beneath the middle of the lower jaw, a pair of long barbs ; 

 no spine on the opercule ; three rays in the brauchial membrane ; the head 



and body covered with large and loosely attached scales ; dorsal fins two, 

 distinct from each other ; ventral beneath the pectoral fins. 



1. TRIGLA (Gr. rptie. three) on account of its three loose pectoral rays. 

 Head nearly square, covered with bony plates, muzzle cleft, forming two 

 projecting and denticulated lobes ; teeth in both jaws and in front of the 

 vomer very numerous, small, and pointed ; the suborbital and opercular 

 bones spiny, and a spine upon the shoulder ; dorsal fins two, the- rays of 

 the first spiny, and of the second flexible ; pectoral fins large and long, their 

 lower three rays detached and distinct ; gill aperture large ; branchial ravs 

 seven ; body lengthy and roundish ; caudal end of the lateral line forked. 



2. DACTYLOITERCS. General characters same as Trigla; pectoral tins 

 fan-like and very large. 



1. SCI.SNA. Head bulky, entirely covered with scales, supported l'\ 

 cavernous bones ; under part of the lower jaw studded with ]>oies ; no teeth 

 on the tongue, vomer, or palatine bones ; edges of the jaws armed with 

 teeth ; preopercule denticulated ; opercule terminating in points ; bran- 

 chial rays seven ; dorsal fins two. 



2. AMPHIPRION. Preorculum, and three operculum pieces denticulated, 

 the later produced on a single row of blunt teeth. 



PERCOIDA; TRIGLOIDA; SCI^ENIDA. DESCRIPTION OF SPECIES. 

 PERCA Perch. All the large group of fishes of which this genus is 

 composed is predaceous as the pointed form of their teeth indicates, and almost 

 all live either in fresh-water lakes and rivers, or at the mouths of the latter 

 where emptying themselves into the sea. They are pretty generally spread 

 over the globe, and are much esteemed for food, being mostly of a fine 

 flavour, and easily digested. From some minor differences they have been 

 divided into five subgenera. 



Skeleton of Perch. 



The Common Perch (P. Fluviatilis) is about fourteen inches in length, 

 and occasionally eighteen or twenty inches ; its colour on the back is deep 

 green, golden lower down, dingy-white on the under parts ; from the back 

 descend five or six deep greenish bands, which gradually are lost on the 

 sides ; the first dorsal fin is violet, with a large black spot between the 

 twelfth and fourteenth rays, and sometimes it lias dark patches on other 

 parts; the second inclining to greenish-yellow; the pectorals transparent 

 and reddish-yellow ; the ventrals, anal, and edge of the caudal bright ver- 

 milion, the rest of the latter deep red inclining to black at its base. 



TRACHINUS Weever. The name Trachinus has been applied to the 

 genus by Artedi, from its trivial Italian name trascina or traschina, a pre- 

 sumed corruption of cpaKaivu, its modern Greek name. In Provence it is 

 called Araignee or Aragno, and in Spain Aragna or Aragniol, from tin- 



